Optical aiming devices, such as rifle scopes or spotting scopes, may be used in a wide range of lighting conditions. In low light conditions, it is helpful to illuminate a reticle pattern to create a greater contrast with a dark background in the field of view. It is also beneficial to illuminate a reticle pattern, or a particular portion thereof, in very bright light conditions. However, the light sources typically used for reticle illumination (e.g., a light emitting diode (LED)) may not have sufficient intensity range to properly illuminate the reticle pattern, particularity in very bright conditions, because the emitted light is dispersed to flood the reticle structure.